WANTED: Outdoor Satsuki Azalea

jan27May 7, 2010

I just received my bonsai Azalea by mail from my son for Mothers Day. The outside temp. is in low to mid 40s. Night will be even lower temps this weekend with possible snow. Should I still put out on covered porch which is eastside & cover at night, or keep in house until temps. are warmer. Plant has beautiful dark green leaves with a few pink flowers. It was grown in MS which I'm sure has warmer temps. Thanks for helping. My plants do well but this is a new & very different challenge for me. My son obviously has faith in me! Thanks so much for advise.

The answer depends on the type of azalea. Some are more cold-hardy than others. In general, azaleas will be fine in the 40s. Even a hard frost, although it may damage or discolor some leaves, won't kill the plant.

However, there are some species that can be affected, especially in the spring. What can happen is that an azalea that has successfully wintered in sub-freezing temperatures will begin to sense the onset of spring and run its sap before nature has finished sending sub-freezing temperatures at it. This means the bark has fluid transferring within it as the plant gears up for spring that was not present during the winter. Then, if a late freeze occurs, the sap freezes which kills the bark, literally tearing it up at the cellular level.

The results of this damage are not immediately apparent. It may take months or even seasons to notice, but you will see the bark, mainly near the soil surface, start to split and/or peel away from the trunk. That means it has been damaged. If the area of damaged bark completely girdles the trunk, everything north of the girdle will die.